The marrow transplantation is performed on a patient suffering from a deficiency or defect in immunocompetent cells or hematopoietic cells aiming to reconstruct functions of the bone marrow by transplanting their normally functioning stem cells (the bone marrow).
Therefore, the marrow transplantation is not only applied to the treatment of primary or secondary deficiencies or defects of hematopoietic tissues or immunocompetent cells, but also, in recent years, has been widely employed in chemotherapy of malignancy for the purpose of reconstruction of those tissues or cells which are damaged together with the tumor cells as a result of the immunosuppressive therapy in expectation of more potent antitumor effects.
The diseases for which the marrow transplantation is performed include primary immunodeficiency disease, semi-aplastic anemia, hereditary progressive hemocytic functional abnormality and, in addition, tumors in the hematopoietic organs, such as acute leukemia, chronic leukemia, malignant lymphoma, plasmocytoma, progressive malignant solid tumor, etc.
Thus, the marrow transplantation is a powerful means of today for treatment of hematopoietic diseases. However, the tranplanted bone marrow cannot always perform its proper functions.
The bone marrow transplantation for a hematopoietic disease is performed when the patient is at a considerably low leucocyte level, and such a low leucocyte level is maintained for a considerably long period even after the transplantation. During this period, the patient is in danger of infectious diseases.